One of the difficulties which is encountered with latches of known type is that, being subject to weathering they are likely to become ineffective. For example hinged latch members or sliding latch members are likely to become only partially effective when the working surfaces become covered with dust or corrosive oxides. Thus it is quite probable that a normal type of latch will have the latch member only partially engaging the striker plate, with the result that dislodgement is relatively easy to effect and some hazard may exist. The main object of this invention therefore is to provide improvements whereby the latch is less liable to failure than many previously proposed latches.